This invention relates to a low current, high voltage power supply for neon signs or other similar gas discharge devices and in particular to a solid state power supply which is far more efficient and less costly than conventional high voltage transformers used to excite gas discharge devices.
Gas discharge devices, such as tubes for neon signs, require a high voltage, typically between five to ten thousand volts or more, to stimulate the gas atoms therein sufficiently to emit radiation in the visible spectrum. In prior art neon tubes used in signs and the like, such high voltages are generally produced by a low frequency step-up transformer connected to a standard 60 Hz power line. However, due to the core requirements of power transformers designed to operate at such low frequencies, the resulting transformers are expensive, heavy and generally bulky.
In addition, since neon signs are usually placed in exposed areas such as store front windows, the likelihood of electrical shock due to inadvertent contact with the high voltage sign interconnections is increased. It is well known that inadvertent contact with low frequency voltage sources, such as conventional 60 Hz line power, generates a far greater hazard of serious injury or death than contact with a high frequency source of comparable voltage. Thus, a power supply of higher frequency provides an additional measure of safety over conventional transformers particularly in those environments where complete isolation of a neon sign from inadvertent human contact is not feasible.